Pneumatic dispatch tube apparatus



March 20, 1934.

J. T. NEEDHAM 1,951,434

7 PNEUMATIC DISPATCH TUBE APPARATUS Filed June 20, 1930 4 Sheets-Sheet 1 Z 5 Z J El W/ A Z INVENTOR k k\ I BY \JOHN T. NEEDH/Mjl v ATTORNEYS March 1934- J. T. NEEDHAM PNEUMATIC DISPATCH TUBE APPARATUS 4 Sheets-Sheet 2 Filed June 20, 1930 ENTOR N T. N EDHAM ATTORNEYS March 20, 1934. J NEEDHAM PNEUMATIC DISPATCH TUBE APPARATUS Filed June 20, 1930 4 Sheets-Sheet 3 INVENTOR \JOHN T. NEEDHAM ATTORNEYS March. 20, 1934.

J. T. NEEDHAM PNEUMATIC DISPATCH TUBE APPARATUS Filed June 20, 1930 4 Sheets-Sheet 4 III; (III z? ,1!!! f X 5 56 /9 25 26 I Q WI) ATTORNEYS Patented Mar. 20, 1934 UNITED STATES PATENT. OFFIE General Conveyors Limited, Montreal,

Quebec, Canada, a corporation. of Canada Application June 20, 1930, Serial No. 462,541

36 Claims.

This invention relates to a pneumatic dispatch tube apparatus of the type disclosed in my pending patent application, Serial No. 394,787. Important objects of the invention are to provide improvements in said apparatus rendering it more eflicient and reliable, and to provide it with improved features of design and assembly.

In the drawings:

Fig. 1 is a diagrammatic view of a pneumatic dispatch tube system embodying my invention;

Fig. 2, a side view of an improved switch device forming part of the system;

Fig. 3, a view of another side of said switch device partly in section;

Fig. 4, a vertical sectional View of the switch device;

Fig. 5, a vertical section taken approximately on the line 5 of Fig. 4;

Fig. 6, a plan view of the station selecting valve device for operating the switch devices;

Fig. 7, an elevation of said valve device, partly in section;

Fig. 8, a horizontal section taken on the line 8-8 of Fig. '7;

Fig. 9, a vertical section taken on the line 9-9 of Fig. '7 showing one of the valves depressed to select a station and operate a switch;

Fig. 10, a vertical section taken on the line 10 of Fig. 7 showing another valve in elevated normal position; and

Fig. 11, an elevation of one of the switch devices and the valve device operatively connected to it.

As shown in Fig. 1, my dispatch tube system includes a central station C located upon one floor of a building, a blower B and a motor M for driving it located adjacent the central station, and pneumatic tubing connecting the blower with the central station and leading through a shaft S and past a number of other floors of the building. The tubing is adapted to receive carriers, from stations at the various floors, for transmission to the central station and to conduct the carriers from the central station back to the outlying floor stations. The arrangement of the system shown in the diagram, however is purely illustrative and may be varied to suit diiierent requirements.

The tubing of the system includes a carrier dispatch tube 1 which leads from a receiving and sending station 2 at the most remote station, upwardly to the central station C. Here it is connected to a discharge terminal 3 and to the vacuum or suction side of the blower. At each floor the tube 1 is provided with a sending inlet 4 for the insertion of carriers into the tube.

These inlets are provided with airtight closure means of any suitable design. At the outermost station 2 the tube is connected to a sending inlet 5. Also included in the system is a carrier dispatch tube 6 for conducting carriers from the central station to the various floors. Tube 6 extends through the shaft S and its upper end is connected to a sending terminal device 7 located at the central station. Through said device the tube 6 is connected with a branch tube or pipe 8 leading to the pressure side of the blower B. At its lower end the tube 6 leads into a carrier receptacle at the lowermost station 2 and through the latter has an air connection with tube 1 to complete an air circuit.

Above each floor to which carriers are to be delivered from the central station the return tube 6 has connected to it a pneumatically operated switch device 9 for diverting a carrier laterally away from the tube to a terminal at the floor; The tube 6 is formed of sections which are connected together by these switch devices. Each device includes a union casing 10 having an open, flanged upper end 11 for connection with the tube section above it and having an open, flanged lower end 12 for connection with the tube section below it. The casing is formed so that its connections with said tube sections will be, in direct vertical alinement. Adjacent connection 12 the lower end of the casing is flanged and formed with an opening as at 13 for connection at a laterally offset point with a branch terminal tube 14. The latter leads downwardly and laterally to a terminal casing 15 accessible from the floor. The tubes 6 and 14 may be secured to the switch casing in any suitable manner. In the presentv instance the tube ends are soldered into flanged collars which are bolted to the flanges of the switch casing. The tubes of the system are in the present case elliptical in-cross section but this shape may be'varied.

Within the switch casing 10 is a straight switch tube 16 which extends between the upper tube connection 11 and the lower tube connections 12 and 13. The casing is formed near its upper end with a cylindrical enlargement 17, and the switch tube is formed at its upper end, as at 18, for a snug swivel fit within said enlargement. Fixed to or formed upon the switch tube are two oppositely extending trunnions 19 having a transverse axis coincident with the axis of said cylindrical enlargement. The casing includes a face plate 20 which forms one wall thereof and is detachably held to the body of the casingby screws 21. Formed upon said face plate and upon the with two air pipe connections 40 and 41.

opposite wall of the casing are two cup-shaped bearing'recesses 22 in which are mounted ball bearings 23 for supporting the trunnions 19. Thereby the switch tube is pivotally supported 'with its upper end in constant communication connections 11 and 12 being in direct vertical alinement so that there are no bends in the dispatch tube line at the points where the switch devices are connected into the line. Thereby travel of the carriers along the line is facilitated. In another position of the switch tube its lower end communicates with the branch tube 14 at the connection 13 to divert a carrier from the tube 6 to the terminal 15. To provide clearance for the swing of the switch tube to this position the switch casing flares downwardly and in order to stop the switch tube accurately in either of its two positions it is provided at opposite sides with stops 2 4 to abut stops 25 upon the inner walls of the casing. From an intermediate point in its length the switch tube flares upward slightly to its upper end to provide clearance for the carrier to enter the switch in either position of the latter. The lower end of the switch tube is provided. with. arcuate bafiies or closure plates 26 which extend from opposite sides of the tube and are adapted to close the connection 13 when the tube is in register with connection 12 and vice versa. At opposite sides of the connections 12 and 13 the switch casing is formed with hollow arcuate extensions 27 providing clearance for said baffles. The removable face plate 20 is formed with extensions which close said casing extensions.

The switch tube is operated or shifted back and forth pneumatically by means including a diaphragm chamber which is defined by two square cup-like sections 28and=28 bolted together and clamping a diaphragm 29 therebetween. Formed upon section 28 is a bracket plate 30 which is mounted upon the outer face of the removable plate 20 of the switch casing and detachably secured thereto by screws 31. Section 28 is also centrally provided with a stuffing box 32. The central portion of the diaphragm is clamped between plates 33 and operatively connected thereto is a push and pull rod 34 which is slidably fitted in said stufiing box, extends across the plate 20, and is slidably supported for straight longitudinal reciprocation through a guide bracket 35 detachably mounted upon said plate. One of the trunnions 19 projects outwardly through an aperture in the face plate 20 and has an operating arm 36 detachably fixed to it and extending downward toward the rod 34. At its lower end said arm is formed with a fork 37 which straddles a roller 38 'mounted upon a lateral arm 39 detachably carried by the rod 34. Thereby the pull rod is operatively connected to said operating arm and the switch tube for swinging the latter as the diaphragm is flexed. The supporting bracket 30 of the diaphragm chamber is provided From connection 40 a passage 42 leads into the chainber section 28 and from connection 41 a passage 43 leads into the chamber section 28 When air pressure is admitted to chamber section 28 and exhausted from section 28 the d alphragm will be flexed to the right with reference to Fig. 4 and the switch tube will be rocked into communication with the branch tube 14. When air pressure is admitted to chamber 28 and exhausted from chamber 28 the diaphragm will be flexed to the left and the switch tube will be swung to normal position to connect the sections of the transmission line.

The switch operations are controlled by a valve device 44 located at the central station C of the system. This device includes a casting 45 forming a valve casing. Said casting is horizontally elongated and rectangular in contour. At one face it is covered by a plate 46 detachably held to the casing by screws 47. A substantially U- shaped channel 48 is formed in said face of the casting and covered by plate 46 and forms a manifold for leading air under pressure to a series of valves mounted in the casing. Channel 48 has a vertical portion 43 adjacent one end of the casting and two horizontal branches 48 and 48 leading from the upper and lower ends of the portion 43 for most of the casting length. An air pipe connection 49 formed in the face plate 46 opens into the channel portion 43 In the same face of the channel a straight horizontal channel 50 is formed midway between the channel branches 43 and 48. Channel 50 is entirely separated from the U-shaped channel 43 and forms a vac uum or suction chamber. The face plate 46 is formed with a suction pipe connection 51 opening into one end of channel 55.

Formed in casting 45 is a series of cavities 52 arranged in a straight horizontal row between the channel 50 and the upper branch channel 48 A similar row of cavities 53 is formed in the casting between the channel 50 and the lower branch channel 48 with each cavity located directly be-.

A series of vertical valve-receiving bores 5'7 are formed in casting 45 at points spaced therealong corresponding to the spacing of the cavities 52 and 53. Each bore extends downward from the upper surface of the casting, crosses the channels 48*, 5e and 48, one of the cavities 52 and one of the cavities 53 and opens into the lowermost channel 56. Fitted in each bore 57 for vertical reciprocation is a tubular valve 53. There is one of these valves for each switch device 9 in the system. At its upper end each valve is closed by a plug 59 which has a head to bear against the upper face of the casting and limit the depression of the valve. The lower end of the valve projects into channel 56 and is closed. and rounded as at 60.

Substantially midway its length the interior of the valve is divided by a partition plug 61. Above said plug the valve is formed with apertures 62 and below the plug the valve is formed with apertures 53. In its normal position the valve is elevated, as shown in Fig. 13. Then, the apertured portion of the valve above the plug 61 places the air pressure channel 48 in communication with cavity 52 crossed by the valve while the apertured portion of the valve below said plug places the suctionchannel 50 in commiuiication with cavity '53. When the valve is depressed into a station-selecting position, as shown in Fig. 9, the apertured portion of the valve above plug 61 places suction chamber 50 in communication with cavity 52 and the apeitured portion below the plug places the air pressure channel 48 in communication with cavity 53.

A series of levers 64 for depressing the valve 58 are pivotally mounted at the upper edge of face plate 46. Each lever extends from its pivot '65 forwardly across the upper end of the valve and carries a roller 65 for engaging the head of valve plug 59. The lever is formed with a stop edge to engage the top of the valve casing and limit its downward throw. Engaging said stop edge is a plunger 6'? mounted to reciprocate in a bore in the casing and yieldably pressed upwardly by a spring 68. When the handle is released the spring pressed plunger automatically elevates it to normal position. There is a lever for each outlying station along the shaft S, and when a station is to be selected for receiving a carrier the appropriate lever is depressed for operating the particular switch 16 serving said station.

It is necessary that all of the tube switches 15 except the selected one should be in normal position, and improved means are provided to automatically ensure this. Within the channel 56 of. the valve casing, below the valves, is an end less chain 69. This chain is trained around two end pulleys '70 disposed at opposite ends of said channel and its upper strand is trained over a series of intermediate pulleys 71 equally spaced apart between the end pulleys. One end pulley is mounted in a fixed position, within the channel, while the other end pulley is mounted upon a block 72 which is slidably mounted in the channel for limited movement toward and from the fixed pulley. Said block is formed with slots '73 through which headed screws '74 are passed and threaded into the valve casing. Detachably secured to the casing inwardly of the slidable block is a bracket '75 through which an adjust-- ing screw '76 is threaded. Said screw has a swivel connection with the block whereby the latter may be adjusted toward and from the fixed pulley. By tightening the screws '74 the block may be held in adjusted position.

The intermediate pulleys '71 are mounted in fixed positions intermediate the valves 58 and the upper strand of the chain is trained over the pulleys and under the rounded lower ends 60 of the valves in a serpentine course. The chain has a limited degree of slack which is sufficient to permit only one valve at a time to occupy a d pressed station selecting position. When another valve is depressed a tension is exerted upon the chain which automatically restores a previously operated Valve to normal elevated position, for returning a tube switch controlled thereby to normal position. A particular advantage of the endless chain is that it offers the same resistance to the depression of each valve.

The valve device is pneumatically connected to the pressure side of blower B by a pipe '77 forming a branch of pipe 8 and leading to connection 49 communicating with a U-shaped channel is of the valve casing. A pipe '78 forming a branch or" pipe 1 connects the valve device to the vacuum or suction side of the blower and leads to pipe connection 51 opening into channel 50.

In the present disclosure there are five switch devices 9 and six valves 58. Five of these valves are pneumatically connected to the switches for operation of the latter. Each valve of said five is pneumatically connected to the "switch device which it operates by a pair of pipes '79 and 80. Pipe 79 leads from the pipe connection 54 of the cavity 52, at the valve, to pipe connection 4'0 and one side of the switch operating diaphragm, and pipe 80 leads from pipe connection 55 to cavity 53 to pipe connection 41 of the switch, and the opposite side of the diaphragm. The sixth valve corresponds to the most remote station 2. Since said station has no switch device 9, no pneumatic connections are required between the sixth valve and station 2 and the .pipe connections 54 and 55 of said valve may be plugged; or, the ports of the valve may be plugged or blanked. Said sixth valve serves to return a previously operated one of said five switch-operating valves to normal position. When said sixth valve is depressed it exerts a tension upon chain 69 which returns any one of the previously depressed other valves to normal position. This ensures that all of the carrier switches will be positioned to permit transmission of a carrier from the central station clear to station 2.

Each time that a valve lever 64 is depressed an electric circuit, not shown, for controlling the motor M is closed and the blower B is started to effect the pneumatic operation of the selected switch and the propulsion of a carrier to its destination. The closing of said circuit is caused by a switch 81 which includes a pair of spaced spring terminals 82 mounted upon an insulation bracket 83 located below the valve levers and attached to the valve casing. Each lever carries an insulated contact 84 which, in the depressed position of the lever, is inserted between the spring terminals 82 to electrically connect them. There is one of these switches, with its circuit connections, for each lever, and they are housed by a box like casing 85 detachably secured as at 86 to the valve casing and also covering the channel 56.

In the operation of the dispatch tube system, a carrier is placed in the tube through any one of the sending inlets for transmission to the receiving terminal 3 at the central station. From the central station the carrier is transmitted to its destined outlying station through the tube 6. First, the carrier is placed in the sending device '7, then an appropriate one of the valveoperating and station selecting levers 64 is depressed. This closes one of the switches 81 and causes the starting of the motor M for driving the blower B. The valve 58 beneath said lever is also depressed and effects a vacuum connection between the blower and the selected switch device through the channel 50, the portion of the valve above the plug 61, the cavity 52 and the pipe 79 connected to the right hand side of the diaphragm chamber of the selected switch, with reference to Fig. 4. Simultaneously the pressure side of the blower is connected to the opposite side of the diaphragm chamber through the channel 48 of the valve device, the apertured portion of the depressed valve below the plug 61, the cavity 53 and the pipe 80. There is then pressure to the left of the diaphragm and vacuum or very low pressure to the right of the diaphragm so that the latter is flexed to the right and causes the swinging of the switch tube 16 into register with pipe connection 13, for the diversion of a carrier from the tube line 6 to the branch tube I l and the discharge terminal 15.

The valve 58 just operated, is returned to its upper, normal position by the subsequent operation of another valve and the pull of the chain 69 as previously described. In its upper position the valve reverses the pressure and vacuum connections just described, connecting the pressure channel 48 of the valve device to the pipe '79 and the right hand side of the diaphragm, with reference to Fig. 4, and connecting the vacuum channel 50 to the pipe and the left hand side ofthe diaphragm. The diaphragm is thereby flexed to the left and the switch tube 16 is shifted to normal position for conducting the carrier straight along the tube line 6, past the station served by this switch to another station farther down the line. All of the switch-operating valves except the depressed one make these connections with their respective switch devices so that all of the switch tubes except the selected oneare held in normal position.

A by-pass pipe 14 is connected to each branch pipe 14 at apoint just above the terminal 15 and leads to the tube 6. This pipe has a check valve 14 which opens toward the tube 6 and, after the delivery of a carrier to the terminal 15 the air flows back into the main tube through said pipe and check valve. The check valves prevent an undesired flow of air from the pipe 6 to the various terminals, through the pipes 14 When the air has reached the lowermost station 2 via the tube 6 it flows through the carrier receptacle 2 which is normally closed and thence through a short pipe 2 to the transmission tube 1 for return to the blower. The carrier inlet 5 is connected to the transmission pipe just above the juncture of the latter with pipe 2 A depressed valve lever 64 remains depressed only momentarily. As soon as it is released the spring projected plunger 67 elevates it out of contact with the terminal fingers 82. The momentary closing of the switch causes the operation of a timing device, not shown, which determines the duration of the motor operation. The mounting of the valves 58 provides for their easy removal. They are disposed entirely above the chain. 69 and are obstructed only at their upper ends by the levers 64. When the latter are swung out of the way the valves are entirely free for upward withdrawal from the valve casing.

What I claim is:

1. In a pneumatic dispatch tube apparatus, a carrier dispatch tube formed of a plurality of sections supported with their ends spaced apart; a switch tube disposed between the spaced tube ends and mounted to shift to a position connecting the tube sections for the transmission of a carrier along the tube and to shift to a position for the discharge of a carrier from the tube; and fluid pressure operated means to shift said switch tube, comprising means forming a chamber adjacent the switch tube, a shiftable partition wall in said chamber, a pair of fluid connections leading from a point distant from the switch tube to said charm her at opposite sides of said partition wall for shifting the latter in opposite directions by changes in fluid pressure, and an operative connection between, said shiitable partition wall and the switch tube to shift the latter.

2. In a pneumatic dispatch tube apparatus, a carrier dispatch tube formed of a plurality of sections supported with their ends spaced apart; a switch tube disposed between the spaced tube ends and mounted toshift to a position connecting the tube sections for the transmission of a carrier along the tube and to shift to a position for the discharge of a carrier from the tube; and pneumatically operated means to shift said switch tube, comprising means forming a diaphragm chamber, a diaphragm in said chamber, means to establish pressure and suction connections with said chamber at opposite sides of the diaphragm for flexing the latter in opposite directions, a push-and-pull rod operatively connected to the diaphragm and extending outwardly from the chamber, means supporting and guiding said rod for straight longitudinal reciprocation, and an operative connection between said rod and the switch tube for shifting the latter to one of its positions when the diaphragm is flexed in one direction and to its other position when the diaphragm is flexed in the opposite direction.

3. In a pneumatic dispatch tube apparatus, a carrier dispatch tube formed of a plurality of sec tions supported with their ends spaced apart; a switch tube disposed between the spaced tube ends and mounted to shift to a position connecting the tube sections for the transmission of a carrier along the tube and to shift to a position for the discharge of a carrier from the tube; and pneumatically operated means to shift said switch tube, comprising means forming a diaphragm chamber, a diaphragm in said chamber, means to establish pressure and suction connections with said chamber at opposite sides of the diaphragm for flexing the latter in opposite directions, a push-and-pull rod operatively connected to the diaphragm and extending outwardly from the chamber, means supporting and guiding said rod for straight longitudinal reciprocation, and an operative connection between said rod and the switch tube for shifting the latter to one of its positions when the diaphrgm is flexed in one direction and to its other position when the diaphragm is flexed in the opposite direction; and valve means to reverse the pressure and suction at opposite sides of the diaphragm to flex the latter in opposite directions.

4. In a pneumatic dispatch tube apparatus, a switch device comprising a union casing for joining two opposed sections of a pneumatic dispatch tube; a switch tube mounted in said casing to shift to a position connecting the tube sections for the transmission of a carrier along the tube and to shift to a position for the diversion of a carrier from the tube, said casing having a removable wall rendering the switch tube accessible and removable from the casing; and. pneumatically operated means carried by said removable wall for shifting the switch to said two positions.

5. In a pneumatic dispatch tube apparatus, a switch device comprising a union casing for joining two opposed sections of a pneumatic dispatch tube, provided with a connection for one of said tube sections at one end, a connection for the other section at its opposite end alining with the flrst connection, and a terminal connection adjacent to and laterally offset from the first connection; a. straight switch tube pivotally mounted in said casing with one end in constant communication with said first connection and its other end shiftable to register with either the second tube connection or with said terminal connection, said casing having a removable wall rendering the switch tube accessible and removable from the casing; pneumatically operated means for shifting the switch tube carried by said removable wall and comprising means forming a diaphragm chamber, a diaphragm in said chamber, and a push-and-pull rod operatively connected to said diaphragm and guided for straight longitudinal reciprocation; an operative connection between said rod and the switch tube for shifting the latter; and means to establish "pressure and suction connections with said chamber at opposite sides of the diaphragm for flexing the latter in opposite directions.

6. In a pneumatic dispatch tube apparatus, a dispatch tube line; a plurality of pneumatically operated switch devices connected into said line at spaced points therealong and operable to permit a carrier to pass along the line or to divert it to a selected station; and a device for independently operating said switches and selecting stations to which carriers are to be diverted, comprising a plurality of adjacent shiftably mounted valves each provided with air connections with one of the switches for operating it and having a normal position for positioning its connected switch for transmission of a carrier along the line and a station selecting position to operate the switch for the diversion of a carrier, and an endless flexible band to control the shift of said valves, trained for engagement with the latter at spaced points and supported between its points of engagement with the successive valves and having a limited slack to permit only one valve to occupy a station selecting position at a time and operating to automatically restore a previously operated valve to normal position when another valve is shifted to station selecting position.

'7. In a pneumatic dispatch tube apparatus, a dispatch tube line; a plurality of pneumatically operated switch devices connected into said line at spaced points therealong and operable to permit a carrier to pass along the line or to divert it'to a selected station; and a device for independently operating said switches and selecting stations to which carriers are to be diverted, comprising a plurality of adjacent shiftably mounted valves each provided with air between its points of engagement with the successive valves and having a limited slack to permit only one valve to occupy a station selecting position at a time and operating to automatically restore a previously operated valve to normal pol sition when another valve is shifted to station selecting position,

and manually adjustable means to regulate the slack in said band.

8. In a pneumatic dispatch tube system including a carrier dispatch tube leading from a central station and provided with a plurality of discharge terminals therealong; a plurality of terminal selectors at the central station each manually operable to cause the diversion of a carrier from said dispatch tube to a selected station; and

. an endless flexible band trained to engage said station selectors at spaced points and supported between its points of engagement with the successive selectors to control said station selectors and permit only one selector to occupy a station I selecting position at a time and to automaticallyv charge terminals therealong; a plurality of terminal selectors at the central station each manually operable to cause the diversion of a carrier from said dispatch tube to a selected terminal; an endless flexible band trained to engage said station selectors at spaced points and supported between its points of engagement with the successive selectors to control said station selectors and having a limited slack to permit only one selector to occupy a station selecting position at a time and operating to automatically restore a previously operated selector to normal position when another selector is operated to station selecting position; and manually adjustable means to regulate the slack in said band.

i A station selecting device for a pneumatic dispatch tube system comprising a casing; a plurality of air valves mounted for vertical reciprocation in said casing; an air pressure chamber in said casing communicating with the valves; a suction chamber in the casing communicating with the valves, pipe connections, two for each valve, carried by the casing, the valve being adapted in one position to place one pipe conne'c' tion in communication with the suction chamber and the other pipe connection in communication with the pressure chamber and in another position to reverse said communications; a chamber formed in the casing and having the lower ends of said valves projecting into it; a row of pulley-s mounted in said last chamber beneath the valves; and an endless flexible valve control band trained around said pulleys with one strand in contact with the lower ends of the valves at spaced points and supported between its points of contact with the successive valves and having a limited slack to permit only one valve to occupy a depressed position at a time and to automatically elevate a previously depressedvalve when another valve is depressed.

11. A station selecting device for a pneumatic dispatch tube system comprising a casing; a plurality of air valves mounted for vertical recipro cation in said casing; an air pressure chamber in said casing communicating with the valves; a suction chamber in the casing communicating with the valves; pipe connections, two for each valve; carried by the casing, the valve being adapt ed in one position to place one pipe connection incommunication with the suction chamber andth'e other pipe connection incommunication with, the pressure chamber and in another position toreverse said communications; a chamber formedin the casing and having the lower ends of said valves projecting into it; a'row of pulleys mounted in said last chamber beneath the valves; an end; less flexible valve control band trained around'said pulleys with one strand in contact with thejlowe'f ends of the valves at spaced'pointsand supported between its points of contact with the successive valvesv and having a limited slack to permit only one valve to occupy a depressed position at a time andv to automatically elevate a previously de pressed valve when another valve is depressed} and manually adjustable means to regulate said slack.

12. A switch device for a pneumaticdispatch tube line; comprising a casing for connecting sec tions of the line; carrier switch means insaid casing operable to permit a carrier to pass" along the line past the switch device or to'divertfa car rier from the line, said casing having a, wall'dis placeableto an open position to give access to the switch means; and means carried by 'saidwall for operating the switch.

13. A switch device for a pneumatic dispatch tube line, comprising a casing for connecting sections of the line; a carrier switch means in said casing operable to permit a carrier to pass along the line past the switch device or to divert a carrier from the line, said casing having a wall displaceable to an open position to give access to said switch means; pneumatically operable means chamber, a shiftable partition wall in said chamber, fluid connections to said chamber at opposite sides of said partition wall for shifting the latter in opposite directions by fluid pressure, said fluid connections leading to a point remote from the switch and an operative connection between said shiftable partition wall and the switch to shift the latter; and manually operable control means at said remote point and connected to said fluid pressure connections to control the fluid pressure therein for operation of the switch.

15. A carrier switch unit for a pneumatic dispatch tube line, comprising a union casing for joining sections of the line; a carrier switch I mounted in said casing for shifting to a position permitting transmission of a carrier along the line past the switch unit and to a position for diverting a carrier from the line; pneumatically operable means carried by the casing and comprising means forming a diaphragm chamber, a

diaphragm partitioning said chamber, fluid connections leading from a remote point to said chamber at opposite sides of the diaphragm, and an operative connection between said diaphragm l and the switch for shifting the latter; and manually operable control means at said remote point and connected to said fluid pressure connection to control the fluid pressure therein for operation of the switch.

16. A control apparatus for a pneumatic dispatch tube system comprising a plurality of terminal selectors operable. for selecting the destination of carriers; and an endless, flexible band position at a time and operating to automatically :1 selecting position.

trained for operative connection to said selectors at spaced points and supported between its points of operative connection with the successive selectors and operative to automatically restore a previously operated selector to normal non-selec-.

tive position when another selector is operated to 17. A control apparatus for a pneumatic dispatch tube system comprising a plurality of terminal selectors operable for selecting the destination of carriers; an endless flexible band trained jto operatively engage said selectors at spaced points and supported between its points of operative'engagement with the successive selectors to control said selectors and having a limited slack permitting only one selector to occupy a selecting restore a previously operatedselector to'normal non-selecting position when another selector is operated to selecting position; and means for adjusting said slack. V

18. A fluid pressure control device comprising a plurality of valves each shiftable to and from a normal position; and an endless flexible valvereturning band trained for operative connection with said. valves at spaced points and supported between its points of operative connection with the successive valves and operative to automatically restore a previously operated valve to normal position when another valve is shifted out of normal position.

19. A control device comprising a plurality of control members each shiftable to and from a normal position; and an endless flexible band trained for operative connection with said control members at spaced points and supported between its points of operative connection with the suc'-. cessive control members and operative to automatically restore a previously shifted control member to normal position when another control member is shifted out of normal position.

20. A control device comprising a plurality of control members each shiftable to and from a normal position; an endless flexible band; pulleys training said band for operative connection with said control members at spaced'points and supporting the band between its points of operative connection with the successive control members, the band having a limited slack to permit only one control member at a time to occupy a position out of normal and to automatically restore a previously operated control member to normal position when anothercontrol member is shifted out of normal position; and means for adjusting one of said pulleys to regulate said slack.

21. A control device comprising a plurality of control members each shift-able to and from a normal position; an endless flexible band; and a series of pulleys training said band for operative connection withsaid control members at points between the successive pulleys and supporting the band between the successive control members, the band being operative to automatically restore a previously shifted control member to normal position when another control member is shifted out of normal position. 7

22. In a pneumatic dispatch tube apparatus, a dispatch tube line; a plurality of pneumatically operated switch devices connected into said line at spaced points therealong and each operable to permit transmission of a carrier along the line or to divert a carrier to a selected station; and a device for independently operating said switches and selecting stations to which carriers are to be diverted, comprising a plurality of adjacent shiftably mounted valves each provided with air connections with one of the switches for operating it and having a normalposition for positioning its connected switch for transmission of a carrier along the lineand a station selecting position to operate the switch for the diversion of a carrier, an endless flexible band to control the shift of said valves, and 'a' series of pulleys spaced along one reach of the band and training and supporting it in operative connection with the valves at points between the pulleys, the band having a limited slack to permit only one valve to occupy a station selecting position at a time and operating to automaticala position for diverting a carrier from the line; and pneumatic mechanism for shifting said switch comprising means forming a diaphragm chamber, a diaphragm partitioning said chamber, means to alternately establish air pressure and suction connections with said. chamber at opposite sides of the diaphragm for flexing it alternately in opposite directions, and an operative connection between the diaphragm and the switch,

24. In a pneumatic dispatch tube apparatus including a tube line having a sending station and a discharge station at an intermediate point remote from the sending station, a carrier switch mounted for shifting to a position permitting transmission of a carrier along the line past said discharge station and to a position for diverting a carrier from the line to the discharge station; and pneumatic mechanism for shifting said switch comprising means forming a diaphragm chamber adjacent the switch, a diaphragm partitioning said chamber, a valve device at said sending station, and a pair of tubes leading from said valve device to the chamber at opposite sides of the diaphragm, the valve device being operable to alternately establish air pressure and suction connections with said tubes for alternately flexing the diaphragm in opposite directions, and an operative connection between the diaphragm and the switch.

25. In a pneumatic dispatch tube apparatus including a tube line having a sending station at one end and a discharge station at an intermediate point, a carrier switch mounted for shifting to a position permitting transmission of a carrier along the line past said discharge station and to a position for diverting a carrier from the line to the discharge station; and pneumatic means for shifting said switch comprising means forming a diaphragm chamber adjacent the switch, a diaphragm partitioning said chamber, a valve device at said sending station, and a pair of tubes leading from said valve device to the chamber at opposite sides of the diaphragm, the valve device in normal position being connected to one of said tubes to maintain air pressure on one side of said diaphragm to hold the switch in normal position and being operable to alternately establish air pressure and suction w connections with said tubes for alternately flexing the diaphragm in opposite directions, and an operative connection between the diaphragm and the switch.

26. A carrier switch device for a pneumatic dispatch tube line, comprising a union casing for connecting sections of the tube line; a carrier switch means in said casing operable for diverting a carrier from the line; a unitary fluid pressure operated means detachably mounted upon the exterior of said union casing and comprising a casing defining a diaphragm chamber, a diaphragm partitioning said chamber and fluid pressure ports leading to said chamber at opposite sides of the diaphragm; and an opera -tive connection between said diaphragm and said switch means to operate the latter as the diaphragm is shifted.

27. A carrier switch device for a pneumatic dispatch tube line, comprising a union casing for connecting sections of the tube line; a carrier switch means in said casing operable for diverting a carrier from the tube line, the casing having a wall displaceable to open position to give access to said switch means; a unitary fluid pressure operated means detachably mounted on said wall and comprising a casing. defining a diaphragm chamber, a diaphragm partitioning said chamber, and fluid pressure ports leading to said chamber at opposite sides of the diaphragm; and an operative connection between the diaphragm and said switch means to operate the latter as the diaphragm is shifted.

28. A control device for a pneumatic dispatch tube system, comprising a plurality of terminal selectors mounted for reciprocation to select the destination of carriers, and a flexible tension strand trained in engagement with one end of each of said selectors and supported between the successive selectors and operative to automatically restore a previously shifted selector to a non-terminal-selecting position when another selector is shifted to a terminal-selecting position, each selector being mounted for removal from the device by endwise shifting away from said tension strand.

29. A control device for a pneumatic dispatch tube system, comprising a fluid pressure casing; a plurality of terminal-selecting valves mounted in said casing for vertical reciprocation to establish fluid pressure connections determining the destinations of carriers; and a flexible tension strand trained in engagement with the lower ends of said valves and supported between the successive valves and operative to automatically restore a previously depressed valve to elevated nonterminal-selecting position when another one of said valves is depressed to terminal-selecting position, each valve being independently removable from. the casing by endwise upward withdrawal away from said strand. 7

30. A control device for a pneumatic dispatch tube system, comprising a plurality of terminal selectors mounted for vertical reciprocation to select the destination of carriers and a flexible tension strand trained in engagement with the lower end of each of said selectors and supported between the successive selectors and operative to automatically restore a previously shifted selector to a non-terminal-selecting position when another selector is shifted to a terminal-selecting position, each selector being mounted for removal by endwise shifting away from said tension strand.

31. In a pneumatic dispatch tube apparatus including a tube line having a discharge station at an intermediate point; a carrier switch operable to permit transmission of a carrier along the line past said discharge station and operable to divert a carrier from the line to the discharge station; and fluid pressure-operated mechanism for operating said switch comprising means forming a chamber adjacent the switch, a shiftable partition wall in said chamber, an operative connection between said wall and the switch, a valve device at a point remote from the discharge station, and a pair of tubes leading from said valve device to said chamber at opposite sides of the shiftable partition wall, the valve device having a normal position to establish a fluid pressure connection with one of said tubes and establish a suction connection with the other tube to hold the switch in normal position and being operable to reverse said connections, to shift said partition wall and operate the switch.

32. In a pneumatic dispatch tube apparatus including a tube line having a discharge station at an intermediate point, and a pump connected to said line to produce a carrier-propelling flow of air in the line, a carrier switch operable to permit transmission of a carrier along the line past said discharge station and operable to divert a carrier from the line to the discharge station; and a pneumatic mechanism for operating said switch comprising means forming a chamber adjacent the switch, a shiftable partition wall in said chamber, an operative connection between said wall and the switch, a valve device at a point remote from the discharge station, and'a pair of tubes leading from said valve device to said chamber at opposite sides of the shift-able partition Wall, the valve device being operable to simultaneously establish an air pressure connection between the pump outlet and one of said tubes and a suction connection between the pump inlet and the other tube and being operable also to reverse said connection, to thereby shift said partition Wall in opposite directions to operate the switch.

33. In a pneumatic dispatch tube'apparatus including a tube line having a discharge station at an intermediate point, a carrier switch operable to'permit transmission of a carrier along the line past said discharge station and operable to direct a carrier from the line at the discharge station; and fluid pressure-operated mechanism for operating said switch comprising means forming a chamber adjacent the switch, a shiftable partition wall in said chamber; an operative connection between said wall and the switch, a valve device at a point remote from the discharge station, and a pair of tubes leading from said valve device to said chamber at opposite sides of the shiftable partition wall, the valve device being operable to vary the fluid pressure 35 in said tubes to shift said partition wall and operate the switch.

-34. A control device comprising a plurality of control members each shiitable to and from a normal position, an endless flexible band and pulleys training said band for operative connec tion with said control members at points spaced being mounted for shifting transversely of the general direction of the band at said spaced points and the band having a limited'slack to permit only one control member at a time to occupy a position out of normal and to automatically restore a previously operated controlmeme her to normal position when another control member is shifted out of normal position.

35. In combination, a dispatch tube apparatus, having carrier delivery connections with a plurality of diiferent stations; and a station selectingdevice to control carrier transmission through the apparatus, comprising a plurality of stationselecting members each shiftable to a selecting position for transmission of a carrier to a selected station, an endless band, and means training said hand for operative connection with the station selectors at points spaced along the band andsupporting the band between its points of operative connection with the successive selectors, the band being shiitable around said training means and having a limited slack to permit only one selector at a time to occupy a station selecting position and to automatically restore a previously operated selector to non-selecting position When another selector is shiited to selecting position. v

36. In combination, a dispatch tube line having carrier delivery connections with an end station and with an intermediate station and a switch operable to divert carriers to said intermediate station; and a station selecting device comprising a plurality of shiitable station selectors including a selector for said intermediate station connected to said switch for operating it and a selector for said end terminal, an endless flexible band, and means training said band for operative connection with said selectors at points spaced along the band and supporting the hand between i s points of operative connection with the successive selectors, the selectors being mounted for shifting transversely of the general direction of the band at said points of operative connection and the band being shiftable around its training means and having a limited slack to permit only one selector at a time to occupy a station selecting position and to automatically restore a previously operated one of the selectors to nonselecting position when the other selector is shifted to selecting position.

JOHN T. NEEDl-IAM. 

